Electric and hybrid vehicle propulsion systems typically employ an alternating current (AC) driving circuit, such as an inverter, to convert direct current (DC) voltage of an energy storage device to variable speed AC waveforms to drive an electric motor. The driving circuit usually includes power electronic devices such as insulated gate bipolar transistors (IGBTs) or metal-oxide-semiconductor field-effect transistors (MOSFETs) as switches to construct AC voltages for driving the electric motor by chopping the DC voltage according to a pulse width modulation (PWM) scheme.
The switches in a driving circuit may be turned on/off at appropriate times according to switching signals supplied by a driver integrated circuit (IC). Some driver ICs may be sensitive to electromagnetic noises caused by switching operations, which may interfere with the switching signals supplied by such driver ICs. Signal interference may cause false turning on/off of the switches, which may, in some cases, cause shoot-through events, i.e., both switches in the upper and lower legs of the same phase are turned on. Severe shoot-through events may damage the switches and should be prevented. Therefore, it is beneficial to suppress the switching interference to prevent unwanted noise events that may affect the performance of the switches.